Bentonite lined pond

MitchM's bentonite lined pond


I previously had a 6000 gallon rubber lined pond but decided to remove the liner and replace it with a slightly larger bentonite lined pond. The reason I did this is because I wanted to remove the electrical, plumbing and filtration complexities and instead use a substrate and submerged plant filtration setup that would also allow me to plant various marginals along the edge to try and replicate a wildlife pond.
The pond will get most of it's water supply from our building steel roof rain runoff and I can periodically top off the water level from our water well. Our well water is high in mineral content so that should take care of any mineral requirements the pond may need that rain water doesn't have.
For water movement, I'll be using a couple of 12 inch rubber air diffusers during the summer.

This is what I started with this year.


June 7 we received 6 inches of snow but it was gone in a few days which made for easier weed pulling.


After 2 days of weeding and working with a little Mantis rototiller, the crater was ready for the bentonite.


I used 12 - 50 pound bags of sodium bentonite which gave me about 2 pounds per square foot coverage.


After it was spread out and mixed into the top few inches of soil, it looked a bit like a concrete liner.



I put in 3 wheelbarrow loads of garden soil and mixed it in a bit with the bentonite.


Mixed in with the odd thundershower, we have a few days of nice weather followed by a week of rain, which will be perfect.
As the rain comes and goes, there are a few bare spots in the pond walls that are exposed so I just cover the open areas with more bentonite.


In the meantime, I have the garden hose running at about 1/2 gallon per minute 24/7 to continue filling the pond. Hopefully it should be filled in a week or so.
I've added a few different types of native submerged plants already and I'll be adding more over the next few weeks. I've also added some duckweed and string algae from my indoor aquariums.

Water is already clearing up as of this morning, and there's about 1 foot of water depth already.
There are numerous flies buzzing around the water and I've seen 1 Boreal Chorus frog near the water's edge.
I'll transfer over some minnows in the next couple of days.
There is no shortage of bacteria with the different types of soils already submerged.


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